Method and compositions for protecting maize against injury from the interaction of an organophosphate insecticide-nematicide and an AHAS-inhibiting herbicide using lactidichlor

Abstract

There is provided a method for inhibiting or preventing injury to a corn plant caused by the synergistic interaction of an organophosphate compound employed for the protection of the plant against attack by insects and nematodes and the use of an acetohydroxyacid synthase-inhibiting compound employed for the control of undesirable weed species in the locus of the plant comprising the application of an effective amount of naphthalic anhydride, the dipotassium salt of naphthalic acid, dicamba, 2,4-D, dichlormid, butyl 2-[(5-chloro-8-quinolyl)oxy]acetimidate, butyl [(5-chloro-8-quinolyl)oxy]acetate, 1-methylhexyl 2-[(5-chloro-8-quinolyl)oxy]acetate or 1-carbethoxyethyl-3,6-dichloro-2-methoxybenzoate. There is also provided a safened insecticidal composition.

What is claimed is: 
     
       1. A method of protecting maize or corn from injury which comprises applying an effective amount of a safener compound 1-carbethoxyethyl-3,6-dichloro-2methoxybenzoate (1) to the plant seed at a rate of at least 0.2% seed weight or (2), to the plant at a rate of at least 0.125 kg/ha, wherein said safener reduces the phytotoxic synergistic interaction of a phosphorodithioate insecticide and an acetohydroxyacid synthase-inhibiting herbicide selected from the group consisting of sulfonylurea herbicides and imidazolinone herbicides, each of which is applied in conjunction with said safener compound. 
     
     
       2. The method according to claim 1 wherein the organophosphate insecticide is terbufos or phorate. 
     
     
       3. The method according to claim 1 wherein the acetohydroxyacid synthase-inhibiting herbicide is primisulfuron. 
     
     
       4. The method according to claim 1 wherein the safener compound is applied to the corn plant seed. 
     
     
       5. The method according to claim 1 wherein the safener compound is applied to the corn plant. 
     
     
       6. The method according to claim 2 wherein the organophosphate insecticide is terbufos. 
     
     
       7. A composition to protect maize or corn from injury which comprises an acetohydroxyacid synthase-inhibiting herbicide selected from the group consisting of sulfonylurea herbicides and imidazolinone herbicides, in an amount which is phytotoxic in the presence of a phosphorodithioate insecticide, and a safener compound 1-carbethoxyethyl-3,6-dichloro-2-methoxybenzoate in an amount effective to reduce the phytotoxic synergistic interaction of said phosphorodithioate insecticide and said acetohydroxyacid synthase-inhibiting herbicide. 
     
     
       8. The composition according to claim 7 wherein the herbicide is primisulfuron.